Chore: CLI flags and simple argument parsing (--count, --no-ascii, --emoji)

[wiertmir]

Goal

Add simple CLI flags parsing to support demo options: --count N to seed N random monkeys, --no-ascii to suppress art, --emoji, etc.

Why

Makes the app scriptable for demos and CI runs.

Light implementation notes

• Implement a minimal ParseArgs(string[] args) in Program.cs returning an options object.
• Support: --count <N>, --no-ascii, --no-color, --emoji, --repl, --no-anim.
• Prefer not to add a dependency; manual parsing is fine for this small set. Optionally later replace with System.CommandLine.
• Add unit tests for parsing edge-cases.

Files to modify/create

• MyMonkeyApp/Program.cs
• MyMonkeyApp/Helpers/ArgParser.cs (optional)

Labels:["enhancement","feature-request","good first issue","area-console"]